The embodiments of the disclosure relate to a polysilicon thin film and a manufacturing method thereof, a TFT including the polysilicon thin film and a manufacturing method thereof, and a display panel including the TFT.
Low-temperature polysilicon (LTPS) thin film transistor (TFT) are widely used in liquid crystal display panels (LCDs) and organic light-emitting diode display panels (OLEDs) due to its advantages of high mobility, low power consumption, being light and thin, and so on. However, when illumination, high temperature, stress or the like is applied to the LTPS TFT, leakage current significantly increases. This problem impedes the development of low-temperature polysilicon display panels to some extent.
In the prior art, the leakage current of low temperature polysilicon devices is reduced mainly by a method of providing a lightly doped drain region (LDD). As shown in FIG. 1, a lightly doped drain region 2 is provided at positions of a channel region 1 close to a source and a drain of a thin film transistor device and bears partial voltage of the source-drain voltage to reduce the leakage current. However, a mask process would be added in such a method, which increases production cost. In addition, the accuracy of a photoresist mask is about 2 μm, which is difficult to meet the requirements of small-sized channel.